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  <title>分类块级元素</title>
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  <h2>London</h2>
  <p>London is the capital city of England.
    It is the most populous city in the United Kingdom,
    with a metropolitan area of over 13 million inhabitants.</p>
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  <h2>Paris</h2>
  <p>Paris is the capital and most populous city of France.</p>
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  <h2>Tokyo</h2>
  <p>Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
    and the most populous metropolitan area in the world.</p>
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